Keyhole light



May 19, 1942.

A. R. KOEHLER 2,283,444

KEYHOLE LIGHT 2 Sheets-Sheet l Filed April 27, 1940 A. R. KOEHLER 2,283,444

KEYHOLE LIGHT Filed April 27, 1940 2 Sheets-Shet 2 jmmm 1? R11?) efizer Patented May 19, 1942 UNITED STATES T QFEHCE Claims.

manipulated, the device being so constructed.

that it will only function when the lock is in position to secure the door or other member in which it is mounted.

Another object of the invention is to provide a lock keyhole illuminating means which is designed in such a manner that it will only function when the lock bolt is projected, thus enabling one to determine by the process of turning the latch control shaft for the lock, or by other means, whether use of a key in the lock is required.

Still another object of the invention is to provide a door lock device having parts thereof connected in an electric circuit, in which the bolt for the lock functions to prepare the circuit for operation only when it is projected into operating or securing position,

The invention will be best understood from a consideration of the following detailed description taken in connection with the accompanying drawings forming part of this specification, with the understanding, however, that the invention is not to be confined to any strict conformity with the showing of the drawings but may be changed or modified so long as such changes or modifications mark no material departure from the salient features of the invention as expressed in the appended claims.

In the drawings Figure 1 illustrates a lock mechanism constructed in accordance with the present invention.

Figure 2 illustrates a sectional view of a control knob and shaft for the mechanism shown in Figure 1, showing the means for conducting electric current to the incandescent lamp.

Figure 3 is a sectional view similar to Figure 2 but showing a knob of non-conducting material.

Figure 4 is a view illustrating a modification of the invention as shown in Figure 1.

Figure 5 is a view illustrating a further modification of the invention.

reference will first be made to the structure of the invention as illustrated in Figure 1, but it will be apparent from the following description of the modifications of the invention as embodied in Figures 4 and 5 that in all three of the forms illustrated the fundamental feature is present which comprises an insulated conductor carrying bolt which, when projected for engagement with a keeper, prepares the electric circuit of the lock for operation.

Referring particularly to Figure 1, the numeral I generally designatesthe usual metallic housing for a door lock. Such housing has at one edge the face plate'2 which, when the housing is disposed in the chamber 3 formed in the door body, is secured by screws 4 to maintain the housing in operative position.

The numeral 5 designates the usual door knob and shaft controlled latch, while the numeral 6 designates the key controlled bolt for the lock.

, In carrying out the present invention, the bolt 6 has inserted in the end face thereof a contact or terminal 1 which is insulated from the body of the bolt by an insulating sleeve 8 or by any other suitable means. To this contact is connected an end of a current conducting wire 9 which passes through a side of the bolt inside the housing 2 and is arranged so that the bolt may be freely moved back and forth without interference from the wire.

The numeral I0 designates the knob controlled shaft by which the latch 5 is retracted. This shaft has mounted upon its two ends, in the usual manner, control knobs, one only of which is here illustrated as the only one of the knobs which functions as a part of the present invention is the one upon the outer side of the door. This knob is indicated generally by the numeral I l and is shown in detail in Figure 2. The knob II is of hollow construction so as to provide an incandescent lamp chamber [2 and a wall of the knob is provided with a light emitting opening I3 which is normally directed downwardly so that when the lamp enclosed in the chamber is illuminated, the keyhole M of the lock will be illuminated. Within the knob chamber there is formed anincandescent lamp socket [5 in which a lamp, preferably of the 6-8 volt type, is mounted, this lamp being indicated by the numeral l6. One contact or one side of the filament of the lamp is electrically connected with the metallic socket 15. The center contact of the lamp engages a contact I! which is mounted in the end of the shaft l0 and, as shown, the inner end of the knob is provided with an extension sleeve [8 which receives the end of the shaft l and is insulated therefrom as indicated at IS.

The metallic sleeve extension I8 of the knob carries a radially extending contact pin 20. The numeral 2| designates the escutcheon plate which is secured to the face of the door in which the lock is mounted and against which the inner end of the knob bears.

The numeral 22 indicates a pair of resilient electric terminals which are secured in a suitable manner to the housing I so as to encircle the metallic sleeve l8 and be spaced therefrom, as shown in Figure 1. These terminals are brought into relatively closely spaced relation with the contact pin 20, which pin normally extends downwardly and is free of engagement with the terminals, as shown in Figure 1. Thelower ends of the terminals are extended laterally and downwardly, as indicated at 23, and are connected by a contractile spring 24 which tends to draw the terminals together but the extent of movement of the terminals together is limited by an insulation block 25 which is interposed between their lower ends. While any suitable means may be employed for mounting and housin the terminals 22, I have provided the lock housing with a box 26 upon its outer side, which is provided with a removable cover plate 21 and in this box the terminals 22 are mounted upon the wall of the housing, having a suitable body of insulation 28 interposed between them and the housing so as to prevent shorting the terminals.

The current conducting wire extends from the terminal I of the bolt to and is electrically connected. with the two terminals 22 which are adjacent the knob shaft ID.

The numeral 29 indicates a keeper plate which is attached to the frame or jamb of an opening in which the door carrying lock ismounted, such keeper plate being provided with the usual openings 30 and 3| to receive the latch and bolt respectively.

In accordance with the -present invention there is provided a current outlet receptacle upon the back face of the keeper plate 29, such receptacle being indicated generally by the numeral 32. This receptacle comprisesa supporting'plate 33 which is provided with longitudinally extending end slots 34 across each of which is a bar 35 having therein a suitable threaded aperture for the reception of a securing screw 36 which is passed through the plate 29 from the front. The screw passes through a slot 34 and engages the bar 35 and draws the same against the back of the plate 33 so as to hold the latter in proper position so as to aline the opening 31 thereof with the opening 3| of the keeper plate into which the bolt is received.

The receptacle 32 also includes an insulation body 38 which is attached to the rear side of the receptacle plate 33 and which carries the two spring pressed contact pins 39 and 40. These pins extend beyond one end of the insulation body and are directed toward the openings 3 |-3! and are normally urged forwardly by suitable springs 4| which bear against metal terminal plugs 42 which are in electrical connection with the pins, as shown in Figure 1, and each of which is designed or adapted to have a current conducting wire connected therewith. One of such current conducting wires is indicated by the numeral 43 and is electrically connected with the pin 40 and the other wire is indicated by the numeral 44 and is electrically connected with the pin 39.

The receptacle 32 is mounted so that the conductor or contact pin 40 is alined with the bolt carried contact I so that when the bolt 6 is projected into locking position the pin I will make the electrical connection with the contact pin 40 and the other contact pin 39 will engage the end face of the bolt.

With the arrangement described it will be readily seen that when the bolt 6 is in projected or operative position, current may flow from the line 43 to the terminal 1 and to the wire 9 to be carried to the terminals 22 which form one side of a switch of which the other side comprises the knob shaft actuated pin 20. With the bolt projected in the manner stated, if the shaft I0 is turned th pin 20 will come into electrical engagement with one of the resilient terminals 22 and the current from wire 9 will then flow through a terminal 22 to the pin 20 and into the sleeve end of the knob to be carried to one side of the incandescent lamp through the socket 15. The current will then pass out of the lamp through the center contact I l of the shaft I0 and since the shaft H] is electrically joined with the metallic parts of the lock, it will be seen thatthe current will flow back through theseparts' to the bolt 6 and to the return terminal 39 thereby completing the circuit and illuminating the lamp I 6. The light from the illuminated lamp will thus be projected downwardly through the opening l3 to the keyhole I4.

In some types of door hardware the knob is of hard rubber, glass, or other insulation material. Such a knob is shown in Figure 3 and indicated generally by the numeral 45. In this construction the extended portion 43 of the knob will have embedded therein a metallic sleeve 41 which :will form a socket for the incandescent lamp 48.

The movable contact pin 49 which is connected with the knob will be embedded in the material of-the knob also and will be electrically joined with the socket sleeve 41. In this construction, the end of the lock shaft I!) will merely be embedded directly in the material of the knob without requiring the use of other insulation as the material of the knob will effectively insulate it from the sleeve 41, as shown.

In Figure 4 a modified form of the invention is illustrated and in Figure 5 a further modification is also shown. In the forms of the invention illustrated in Figures 4 and 5 it will be noted that the outlet receptacle is of the same form and connected with the keeper plate in the same manner as the receptacle shown in Figure 1. In other words, the same keeper structure and receptacle structure are employed, therefore these parts will be designated by the same numerals by which the receptacle is identified in Figure 1. It will also be noted that in each of the forms of the invention shown in Figures 4 and 5, the bolt for the lock carries an insulated end of a current conducting wire, the same as in the form shown in Figure 1, and functions when projected to prepare the-light circuit for operation. In Figure 4 the lock housing is'indicated generally by the numera1 I while the latch is indicated by the numeral 5' and the bolt by the numeral 6'. The current conducting wire which is attached at one end to the bolt is indicated by the numeral 9, such wire terminating at one end in the protected terminal 1 which has an and exposed through the end face of the bolt. In this form contact pin 54 which extends through a suitable opening in the wall of the housing to the interior thereof and is arranged in alinement with the rear end of the latch so that when this latch is forced rearwardly by rotating the door knob controlled shaft 55, it will come into electrical contact with the contact pin 54. This pin is electrically connected through the sleeve 56, in which it is housed, and the plate 51, with the wire 5| through the medium of the terminal screw 53 which is attached to the plate 51. With the construction shown in Figure 4 it will be seen that when the latch 5' is shifted rearwardly by turning the shaft 55, assuming that the bolt 6' is projected into working position for preparing a circuit for operation, current will flow from the outlet receptacle contact 40 through the wire 9 to and through the lamp 511 to the terminal 58 from where it will pass to the terminal pin 54 and be grounded to the housing through the latch 5' to return by way of the bolt 6' and the contact pin 39, thus illuminating the keyhole opening.

In the form of the invention shown in Figure 5, the lock housing is indicated generally by the numeral I", the latch being designated 3" and the bolt 6". In this form of the invention the wire which is connected at one end with an insulated terminal 1" carried by and exposed through the forward end of the bolt, is indicated by the numeral 9" and leads to and through a switch button 59. This button is mounted at any convenient point on the door, it being here shown as mounted upon the escutcheon plate 60 and controlling the flow of current to an incandescent lamp 6! which is arranged to illuminate the keyhole opening 62. The other side of the lamp 6! from the switch button 59 is grounded to the lock casing I" by the wire 63 and the terminal 64. With this arrangement it will be seen that the illumination of the lamp 6| is not controlled by the turning of the door knob shaft but is controlled by the push button 59. Thus when the door is locked or, when the bolt 6 is projected,

the keyhole opening may be illuminated merely by pressing the button 55.

From the foregoing it will be readily apparent that by the provision of the present invention the insertion of a key in the lock keyhole will be greatly facilitated by reason of the fact that such keyhole can be quickly illuminated and will also be of assistance in indicating either by turning of the knob or pressing of the button 59 whether use of a key is necessary for opening the door or other closure member in which the lock may be mounted.

In Fig. 1 there has been illustrated conventionally a source of electric current in the form of a battery designated by the numeral 65, but it will be readily appreciated that any suitable source of electric current may be made use of for operating the key hole illuminating lamp as, for example, the wires 43 and 44 may be connected in circuit with a suitable 6-8-volt door bell transformer coupled with the usual lighting circuit for the house in connection with which the mechanism is used.

I claim: w

1. In a lock structure including a metallic housing having a keyhole opening, a bolt and a keeper plate for and having an opening to receive the bolt, an electric current'receptacle secured to the back of said keeper and having a pair of electric terminals directed toward said opening one of which is adapted to be engaged by the bolt when the same is projected into the keeper, an electric current conductor having an end attached to and insulated from said bolt and arranged to be electrically connected with the other of 'said terminals when the bolt is projected into the keeper opening, an incandescent electric lamp arranged with respect to said key- 7 hole opening to illuminate the same when energized, said current conductor being connected with one side of said lamp, and means for controlling the fiow' of electric current from the other side of said lamp to said metallic casing for the return of current through the bolt to the first mentioned terminal when the bolt is in projected position in the keeper opening.

2. In a lock structure including a metallic housing having a keyhole opening, a bolt and a keeper plate for and having an opening to receive the bolt, a pair of electric terminals supported by said keeper and directed toward said opening and connected with opposite sides of a source of electric potential, said terminals being yieldingly urged toward the adjacent end of the bolt, an electric incandescent lamp disposed with respect to said keyhole opening to illuminate the latter when energizeda current conductor having one end connected with and insulated from said bolt and arranged to be carried by the bolt into engagement with one of said terminals when the bolt is projected through the keeper open ing, said bolt when so projected being brought into electrical engagement with the other one of the terminals, and means by which the other side of said lamp may be electrically connected with the metallic housing and the bolt for the energization of the lamp.

3. In a lock structure including a metallic housing having a keyhole opening, a bolt and a keeper plate for and having an opening to receive the bolt, an insulation body disposed at the back of the keeper plate, a pair of spring pressed terminals carried by the insulation body,

means for electrically coupling said terminals with opposite sides of an electric circuit, a supporting bracket secured to the rear side of the keeper plate and maintaining said body of insulationin a position to direct said terminals toward the keeper opening, said terminals being disposed in the path of the keeper, an electric incandescent lamp disposed with respect to said keyhole opening to illuminate the latter when energized, a current conductor having one end connected with and insulated from the bolt and exposed upon the forwardend of the bolt to be carried thereby into electrical contact with one of said terminals when the bolt is projected through the keeper opening, said bolt when so projected being pressed into' electrical connection with the other one of the terminals, means for effecting the electrical connection of one side of the incandescent lamp with said bolt, the other side of the lamp being electrically connected with said current conductor.

4. In a lock structure including a metallic housing having a keyhole opening, a bolt and a keeper plate for and having an opening to receive the bolt, a reciprocable latch and means for reciprocating the same, a pair of spring pressed reciprocable electric terminals carried by said keeper upon the rear side thereof and directed toward said opening in the line of movement of the keeper bolt, said terminals being adapted for connection with opposite sides of a source of electric potential, an electric incandescent lamp disposed with respect to said keyhole opening to illuminate the latter when energized, a current conductor connected with one side of said lamp and having an end connected with and insulated from the bolt in the forward end thereof to be carried by the bolt into engagement with one of said yieldable terminals when the bolt is projected through the keeper opening, a spring pressed electric terminal supported in the path of movement of the latch to be electrically engaged with the latch when the latter is retracted, a current conductor connecting the other side of said lamp with the latch engaged terminal, and said bolt pressing against the other one of the pair of terminals to establish electrical connection therewith when the bolt is projected through the keeper opening. 7

5. In a lock structure including a metallic housing having a keyhole opening, a bolt and a keeper plate for and having an opening to re ceive the bolt, a bracket secured to the rear side of the keeper plate and including a collar, a body of insulation secured in said collar and having an end directed toward the keeper plate opening, a pair of spring pressed reciprocable terminal pins carried by said insulation body upon the side nearest to said opening and directed toward the opening in the path of movement of the bolt, said terminal pins being adapted for electrical connection with opposite sides of a source of electric potential, an electric incandescent lamp disposed with respect to said keyhole opening to illuminate the latter when energized, a current conductor connected at one end with one side of said lamp and having its other end connected with and insulated from said bolt in the forward end thereof to be carried by the bolt into engagement with one of said terminals when the bolt is projected through the keeper opening, the said forward end of the bolt being brought into electrical connection with the other one of the terminals when the bolt is projected, and means by which the other side of said lamp may be electrically connected with the metallic housing and the bolt for the energization of the lamp.

ARTHUR R. KOEHLER. 

